Recent research has provided a growing body of literature which attributes the activity of some of the newer classes of CNS agents to their selective activation of the serotonin receptor subtype designated the 5-HT.sub.1A receptor. This has been the case especially for compounds such as buspirone (8-[4-[-4-(2-pyrimidinyl)-1-piperazinyl]butyl]-8-azaspiro[4.5]de cane-7,9-dione) and TVX Q 7821 (2-[4-[4-(2-pyrimidinyl)-1-piperazinyl]buyl]-1,2-benzisothiazol-3-(2H)one- 1,1-dioxide hydrochloride). See Eison et al., Pharmacol. Biochem. and Behav., 24, 701 (1986); Dompert et al., Naunyn-Schmiedeberg Arch. Pharmacol., 328, 467 (1985) and Spencer and Traber, Psychopharmacol., 91, 25 (1987). Both of the compounds cited above are anxiolytics which demonstrate binding at the 5-HT.sub.1A site, while other classic anxiolytics, such as the benzodiazepines and pentobarbital, do not act via the 5-HT.sub.1A receptor. Moreover, compounds such as TVX Q 7821 have been found to possess antidepressant activity (see U.S. Pat. No. 4,818,756) while buspirone has been found to be useful in the treatment of sexual dysfunction (see U.S. Pat. No. 4,640,921 (1987)).
Dopamine is known to play a major role in the nigro-striatal pathway for controlling extrapyramidal motor function. Blockade of these receptors by a nonselective potent D.sub.2 -antagonist results in various EPS effects. Compounds used for anxiety with low affinity for D.sub.2 -receptors will be devoid of EPS liability (AbouGharbia, U.S. Pat. No. 4,636,563 (1987)).
Compounds of this invention demonstrated affinity for the 5-hydroxytryptamine-1A receptor site (5HT.sub.1A) and to a lesser extent, for dopamine-2 receptor sites (D.sub.2). Compounds with such a profile provide a treatment for disorders such as anxiety, depression, and sexual disturbances without EPS liability.